Recipe :

First take the fish, wash with little water (Hilsa should not wash thoroughly, its taste will go by washing). Marinate the fish pieces with salt and 1 tablespoon turmeric powder and keep aside for 15 minutes.In the meantime grind the White mustard seeds with little salt & 2 green chills to a fine paste by adding 1-2 tablespoons of water along with it. Add 1 tablespoon of water to the mustard seed paste, mix it and add it to the pan.As you have already added salt in curd & mustard paste, you should not need to add anymore. But if you like to add, you may add as per your taste.Take the marinated Ilish, in a non-stick pan, add the mustard paste, beaten yogurt, little turmeric, slit chilies and 1/2 cup water and marinate all together very gently. Sprinkle the mustard oil on the marination. Adjust the salt to taste.Now cover the pan with a lid. Put the pan on low heat for 20 minutes. After 20 minutes, turn off the heat, open the lid and serve "Doi Ilish" with Steamed Rice.......